Adjustable Mirror Motor Mounting for Laser Printhead

Abstract

A scan unit printhead of an imaging device having an adjustable mirror mounting. The scan unit includes a housing to which a rotatable minor, one or more light sources and an optical assembly are secured. The scan unit also includes a motor for driving the rotatable mirror, a plurality of fasteners for securing the motor to the housing and a plurality of spacers interposed between a base associated with the motor and the housing. The plurality of spacers resiliently bias the base of the motor away from the housing such that each of the plurality of spacers allows relative adjustment of a space between the base of the motor and the housing during a tightening and loosening operation of at least one of the to plurality of fasteners.

Description

CROSS REFERENCES TO RELATED APPLICATIONS[0001]The present application is related to and claims priority from U.S. patent application ser. No. 61 / 659,410, filed Jun. 13, 2012, entitled, “Adjustable Mirror Motor Mounting for Laser Printhead,” and the present application is related to U.S. patent application Ser. No. 13 / 502,157, filed Sep. 30, 2011, entitled, “Laser Scan Unit Housing for an Imaging Device.” The contents of these applications are incorporated by reference herein in their entirety.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT[0002]None.REFERENCE TO SEQUENTIAL LISTING, ETC.[0003]None.BACKGROUND[0004]1. Field of the Disclosure[0005]Example embodiments of the present disclosure relate generally to a laser scan unit for an image scanning device, and more particularly to an adjustable minor motor mounting for a laser scan unit.[0006]2. Description of the Related Art[0007]Multibeam and single beam laser scanners typically include a housing for holding the sca...

AI Technical Summary

Benefits of technology

Example embodiments of this patent improve upon previous laser scan units by providing an adjustable mirror mount to compensate for variations in parts. The scan unit includes a housing, a rotatable mirror, light sources, and an optical assembly. A motor assembly is also included, with a base and fasteners for securing the base to the housing. The scan unit also has a plurality of spacers that act as springs to adjust the space between the base and the housing. This allows for relative adjustment of the fasteners to improve the planarity of the rotatable mirror with respect to a reference map on the housing. Overall, this improved design makes it easier to adjust the scan unit and ensures better accuracy and consistency in the image captured by the laser scan unit.

Problems solved by technology

Such thermoplastic housings disadvantageously shrink non-uniformly during the molding and subsequent cooling process in the manufacture of the housing.

The inconsistencies associated with the molding and cooling of these parts creates two primary issues.

First, part-to part dimensional variation of features for mounting sensitive optical components, such as mirrors and lenses, creates the need for assembly adjustment mechanisms during production as well as for additional components.

Second, during normal operation of electrophotographic printers, the fuser assembly, the laser scanner motor and other printer components and assemblies may create heat.

The complex shape and features of the housing design, with a multitude of flow disruptions and directions, do not expand uniformly when heated, causing the part to warp or change shape along with the absolute expansion of the housing.

This change of size and shape of the housing, which locates the critical laser pointing and focal elements, creates print quality issues associated with change of spot size and location of the laser image on the photoconductive drum, primarily color to color registration of the four color planes (CMYK).

However, one of the challenges to the use of a metal housing is the fairly large tolerance that needs to be allowed.

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